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Presentation on Embedded system:

What is an embedded system??:

What is an embedded system?? An embedded system is a combination of some software and hardware either fixed in capability or programmable that is specifically designed for a particular function. Examples of embedded system are: industrial machines, automobiles, medical equipments,cameras,household appliances,earphone,toys and PDA etc.

Presentation onTraffic signal:

Presentation onTraffic signal

What is traffic signal??:

What is traffic signal?? one of a set of coloured lights placed at cross roads, junctions, etc., to control the flow of traffic. A red light indicates that traffic must stop and a green light that it may go and yellow Light indicates to get ready.

History of traffic signal: :

History of traffic signal: On 10 December 1868, the first traffic lights were installed outside the British Houses of Parliament in London, by the railway engineer J. P. Knight. The world’s first traffic light came into being before the automobile was in use, and traffic consisted only of pedestrians, vehicle, and wagons. Installed at an intersection in London in 1868, it was a revolving lantern with red and green signals. Red meant "stop" and green meant "caution." The lantern, illuminated by gas, was turned by means of a lever at its base so that the appropriate light faced traffic. On January 2, 1869, this crude traffic light exploded, injuring the policeman who was operating it.

Purpose of Traffic Signals::

Purpose of Traffic Signals: Traffic signals manage the right of way at signalized intersections to provide for the safe and efficient movement of vehicles and pedestrians. Traffic engineers and technicians develop and implement signal timing at each intersection to distribute green time amongst the competing traffic flows to provide for efficient operations.

What Are the Parts of a Traffic Signal?:

What Are the Parts of a Traffic Signal? Traffic signals have four main parts: 1. Display 2. Controller 3. Detector 4. Support

PowerPoint Presentation:

Signal display: The signal display is what the motorist sees. A simple signal display consists of three colors: red, yellow, and green. Did you know that in a typical traffic display, the circular indication is 12 inches in diameter. A typical signal display is more than 3 feet tall and weighs up to 50 pounds.

PowerPoint Presentation:

Signal controller: The traffic signal controller is the “brain” at an intersection that tells each signal display when to change colors. computerized traffic signal controllers get real-time information about the presence of vehicles from sensors in the roadway and on poles. Controllers adjust the amount of green time for different movements based on sensor information. The most sophisticated controllers and software programs allow for the coordination of signals along a roadway, so that vehicles can travel through a succession of intersections without having to stop.

PowerPoint Presentation:

Traffic signal controller

PowerPoint Presentation:

Detector: Detectors are used to identify the presence of a vehicle, so that the controller knows how to adjust the amount of green time to provide. There are many types of detectors. One type is known as the loop detector. The square black lines you may see in the roadway as you approach an intersection are the visible part of the loop detector, which is a thin wire buried in the roadway. When a vehicle drives over the loop, it sends a message to the signal controller. The signal controller's software evaluates the messages from all the loops at the intersection and changes the signal timing appropriately. Small TV cameras can also be used to detect vehicles.